Hep C Drug Deal Raises Patient-Choice Concerns

Express Scripts to Direct Patients Toward AbbVie’s New Treatment

At a time when the rising cost of medicines is causing consternation, an exclusive deal between Express Scripts Holding Co., the nation’s largest pharmacy-benefits manager, and AbbVie Inc., a big drug maker, over a new hepatitis C treatment is generating concern about the implications for patient choice.

The deal came after the benefits manager spent a year railing about the prices charged by Gilead Sciences Inc., which until now has had a lock on the market. Fresh off FDA approval for its drug, AbbVie last month offered...